Well tool retrieving apparatus



May 23, 1967 DL E. YOUNG 3,321,017

WELL TOOL RETRIEVING APPARATUS May 23, 1967 D. E. YOUNG WELL TOOL RETRIEVING APPARATUS 2 Sheets-Sheet 2 Filed Oct. 7, 1964 awa/ E. you/7g 4 5 6 9 Y 0 A 0 0 B J wv J 3 u ik J J .J /M 1. 40/ 1 o :2.1i A. .r 6.. L .u ...$1 l 1H.. .,r. d.. ...0. 1 l .,....A.... a 4 ....ufJO.. 7 V 1 un -lvlll x 1 .IH l 11| lf' l -:r E l Mn v .l 6 7 H 2 J 0 4, a 0 0 .J 0 0 0 3 a a 3 3 3 3 a J United States Patent O 3,321,017 WELL TOOL RETRIEVING APPARATUS David E. Young, Bellaire, Tex., assignor to Schlumberger Technology Corporation, Houston, Tex., a corporation of Texas Filed Oct. 7, 1964, Ser. No. 402,101 9 Claims. (Cl. 166-135) This invention relates to apparatus for retrieving well tools within a well bore; and, more particularly, to running-in and retrieving overshots adapted for use with apparatus for packing-off a well bore.

In conducting such well completion operations as acidizing, cementing, or racturing, a full-opening well packer dependently coupled from a tubing string is employed to pack-off the formation interval to be treated from the remainder of the well bore thereabove. Where more than one formation interval is to be completed, it is usually customary to releasably couple beneath the packer a selectively operable, retrievable bridge plug to pack-off the well bore at the lower limit of the formation interval being treated to prevent treating fluids from flowing into the other formations therebelow. The releasable couplings generally employed for this are comprised of a male coupling or fishing neck on the upper end of the bridge plug mandrel which is selectively connected through cooperatively arranged J-pins and J-slots to a tubular female coupling member or over-shot dependently coupled beneath the packer.

The bridge plug is first set at a particular depth and the packer is disconnected therefrom and moved on up the well bore and set where desired. Treating fluids are then pumped downwardly at high pressure through the tubing and packer and introduced into the isolated formation through appropriately placed perforations in the casing. After the well-completion operation has been concluded, the packer is unseated and then shifted downwardly and re-coupled to the bridge plug. The bridge plug is then unseated by properly manipulating its mandrel and either moved to a new position or else removed entirely from the well.

It is not at all uncommon, however, for a substantial quantity of heavy loose materials to settle on top of a bridge plug during a treating operation. Subsequently, when it comes time to retrieve the bridge plug, it is often found that so much debris has accumulated that the overshot beneath the packer cannot be re-engaged with the shing neck on the bridge plug. In such instances, it is customary to attempt to wash-over the accumulated debris so that the releasable coupling members may again be re-connected. Such washing-over is typically carried out by circulating fluids through the tubing as it is being rotated so that cutting teeth around the lower end of the overshot can cut away the accumulated debris.

lt will be seen, however, that once the J-pins enter the open upper end of the I -slots in the fishing neck, the overshot can no longer be rotated relative thereto. Then if the overshot cannot be forced downwardly through the remaining debris far enough to enable the I-pins to be shifted into the closed portions of the J-slots to allow the bridge plug to be retrieved, the overshot can only be reciprocated or spudded with the hope that it will chip away a sufficient amount of debris to enable it to move on downwardly. Where debris has accumulated and hardened around the upper end of the bridge plug, however, it is usually necessary to remove the tubing string, packer and overshot; attach a drilling bit; and then relower the tubing string and bit to drill through the debris and bridge plug.

Accordingly, it is an object of the present invention to provide new and improved overshots which may be con- ICC tinually `rotated to cut away accumulated debris until they are positively re-engaged with a fishing neck of a bridge plug.

This and other objects of the present invention are accomplished by movably mounting on an upright member 0f a well tool a second member adapted to be received within an overshot and operatively coupling the two members together in such a manner that after the overshot has become engaged with the second member, the overshot can still be rotated until it has become securely connected to the well tool member.

The novel features of the present invention are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation together with objects and advantages thereof, may best be understood by way of illustration and example of certain embodiments when taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of one embodiment of an overshot and a shing neck of the present invention;

FIG. 2 is a cross-sectional view of an alternate embodiment of an overshot and a fishing neck; and

FIG. 3 illustrates a typical bridge plug as it is being released by an overshot such as depicted in either FIG. 1 or FIG. 2.

Turning now to FIG. l, a tubular overshot is shown in position on a lis-hing neck 101 extending from the upper end of an upright body of a well tool such as the mandrel 102 of a conventional bridge plug (not shown). As is customary, lateral ports 10.3 are provided through the mandrel 102 at the upper end of an axial bore 104 extending through the mandrel. A slidable valve member 105 over these equalizing ports is arranged to be opened whenever the bridge plug is being traversed through a fluid-filled well bore to enable fluids in the well bore to flow freely through the mandrel bore 104 rather than being forced through the constricted annular space between the casing and the retracted packing means (not shown). Inasmuch as the fishing necks and overshots of the present invention may be employed with any conventional retrievable bridge plug, it is believed unnecessary to devote further attention to the details of the bridge plug.

The fishing neck 101 is comprised of a fixed outer member 106 having an upwardly directed axial cavity 107 into which va rotatable coupling or inner member 108 having a reduced-diameter lower portion 109 is operatively fitted or telescopically disposed. The lower face of the enlarged-diameter upper portion 110 of the inner member 108 is normally engaged with the upper face of an inwardly projecting annular shoulder 111 at the upper end of the outer member 106.

A selectively operable clutch 112 is operatively arranged in such `a manner that normally the inner member 108 is free to rotate relative to the outer member 106 in one direction but is co-rotatively secured thereto in the opposite rotative direction. The clutch 112 is further arranged to corotatively secure the outer and inner members 106, 108 to one another in both rotative directions whenever the inner member is shifted longitudinally upwardly with respect to the outer member.

To accomplish these functions, a plurality of stacked, annular clutch rings 113, 114 are disposed within the annular space 'between the inner wall ofthe outer member 106 and around the inner member 108. Alternate ones 113 of these clutch rings are co-rotatively secured to the outer member 106 and the remaining ones 114 are corotatively secured to the inner member 1083 by appropriately arranged, slida'bly fitted, splines and grooves. Another clutch ring at the upper end of the stack of clutch rings 113, 114 is co-rotatively secured to the inner 3 member 108 by the same spline securing the clutch rings 114.

Complementary shaped teeth 116 having one face inclined and the other face substantially vertical are lspaced around the opposed surfaces of each of the clutch rings 113, 114 as well as on the lower surface of the upper clutch ring 115. A compression spring 117 engaged between an upwardly directed shoulder 118 around the lower end 109 of the inner member 108 and the lowermost clutch ring maintains the teeth 116 of the stacked clutch rings 113, 114 and 115 cooperatively engaged and urges the uppermost clutch ring 115 against a downwardly directed shoulder 119 projecting outwardly from the upper end of the inner member. Thus, with the clutch teeth 116 being shaped and held in engagement in this manner, it will be seen that the inner member 108 is free to rotate independently of the outer member 106 in one direction, but is co-rotatively secured thereto whenever it is rotated in the opposite direction.

As previously mentioned, the inner member of the fishing neck 101 is free to shift upwardly a limited distance relative to the outer member 106. In the normal position 'of the inner member 108, a plurality of upwardly directed, rectangularly formed teeth 120 around the upper face of the uppermost clutch ring 115 are displaced a short distance below a plurality of downwardly directed, complementary teeth 121 formed around the lower face of the annular shoulder 111. Upward shifting of the inner member 108, however, brings the rectangular teeth 120, 121 .into meshing engagement with one another. Thus, since the upper clutch ring 115 is co-rotatively secured by splines to the inner member 108, whenever the rectangular clutch teeth 120, 121 are moved into engagement, the outer and inner members 106, 108 will be corotatively -secured together in both rotative directions.

The tubular overshot 100 having a plurality of cutting teeth 122 around the lower end is arranged to be disposed over the fishing neck 101. J-slots 123 on opposite sides of the enlarged-diameter upper portion 110 of the inner member 108 of the fishing neck 101 are cooperatively arranged to receive J -pins 124 projecting inwardly from the central portion of the overshot 101.

A slidable valve member 105 is operatively arranged around the upper end of the mandrel 102 to be shifted upwardly from its position as shown in FIG. l to cover the radial ports 103 in the mandrel. O-rings 125 fiuidly seal the valve member 105 around the mandrel 102 above and below the radial ports 103 to block fiuid communication through the ports whenever the valve member is shifted upwardly to its closed position.

A group of resilient fingers 126 spaced `around the lower portion of the overshot 100 have longitudinally spaced, inwardly projecting shoulders 127 and 128 operatively arranged thereon to shift the slidable valve member 105. As the overshot 100 is shifted upwardly, the lowermost shoulders 128 on the fingers 126 engage an outwardly projecting shoulder 129 around the upper end of the slidable valve member 105 and carry the valve member upwardly to close the equalizing ports 103. As the overshot 100 is moved upwardly, theV upwardly directed tapered faces of the uppermost finger shoulders 127 will engage and be cammed outwardly by an annular shoulder 130 laround the outer mem-ber 106. This will spread the resilient fingers 126 outwardly -a sufficient distance to allow these lowermost finger shoulders 128 to clear the shoulder 129 around the upper end of the slidable valve member 105 as the overshot 100 is being removed.

Similarly, whenever the overshot 100 is re-engaged over the fishing neck 101, the tapered lower faces ofthe lowermost finger shoulders 128 are cammed outwardly over the upper shoulder 129 of the slidable valve member 105 to allow the fingers 126 to slip over and, upon springing back, re-engage the slidable valve member. As the overshot 100 continues to move on downwardly, the lower face of the uppermost finger shoulders 127 Ithen engages 4. the upper shoulder 129 of the slidable valve member 105 to push that member downwardly and reopen the equalizing ports 103.

Accordingly, it will be appreciated that whenever the overshot is engaged over the fishing neck 101, the clutch teeth 116 will allow the overshot to be freely rotated in one direction relative to the mandrel 102 Ibut prevents its relative rotation in the opposite direction so long as the inner member 108 remains in its normal downward position. Whenever the overshot 100 is picked up to bring the J-pins 124 into the closed portion of the J- slots 123 the inner member 108 is picked up to bring the rectangular teeth on the upper clutch ring 115 into meshing engagement with their mating teeth 121 on the outer member 106 and co-rotatively secures the overshot 100 to the mandrel 102 regardless of rotative direction.

Thus, it will be seen that the clutch 112 will permit the mandrel 102 of the bridge plug to be operatively shifted longitudinally in either direction as well-as rotated in either direction by manipulating the overshot 100 in a predetermined manner. Further, the clutch 112 permits the overshot 100 to be rotated freely in one direction around the fishing neck 101 so that the cutting teeth 122 may be efficiently used to cut away accumulated debris around the upper portion of the bridge plug.

Turning nowto FIG. 2, a second embodiment is illustrated of a tubular -running-and-retrieving overshot 200 of the presen-t invention that is adapted to be received over a fishing neck 201 secured to the upper end of an upright tool body such as the mandrel 202 of a conventional bridge plug (not shown) This fishing neck 201 is comprised of a fixed inner member 203 extending upwardly from the mandrel 202 with a tubular coupling or outer member 204 being rotatably fitted or disposed around the central portion of the inner member. The outer member 204 is secured against longitudinal movement relative to the inner member 203 by one or more set screws 205 projecting inwardly from the lower end of the outer member and slidably received within an annular groove 206 around the inner member. A plurality of spaced .longitudinal slots 207 around the tubular outer member 204 are open at their upper ends and adapted to receive opposed lugs 208 projecting inwardly `from the central portion of the tubular overshot 204. Downwardly directed thread teeth 209 formed around the upper end of the inner member 203 are cooperatively arranged to engage complementary upwardly directed internal teeth in an expansible split-nut 210 received within yan inwardly directed annular recess around the upper portion of the overshot 200.

A clutch 211 comprised of a plurality of stacked, fiat, annular rings 212, 213 disposed in the annular space be`- tween the inner and outer members 203, 204 of the fishing neck 201 releasably secures the members to one another. Alternate ones 212 of these rings are slipped over and co-rotatively secured by splines to the tubular outer' member 204 with the remaining rings 213 being co-y 212, 213 frictionally engaged as well as to urge the upper-- most clutch ring against .a downwardly directed shoulder' 216 projecting inwardly from the outer member.

Once the cutting teeth 217 have cut away some of the debris on top of the bridge plug, the expansible split-nut 210 on the overshot will begin threadedly engaging the threads 209 as the inwardly projecting overshot lugs 208 enter the open upper end of the longitudinal slots 207 around the outer member 204. Even though the lugs 208 are then confined in longitudinal slots 207, the overshot '200 may still be rotated, however, to continue cutting away debris by applying suliicient torque to the outer member 204 to overcome the frictional engagement between the rings 212 with the rings 213 co-rotatively secured to the inner member. Moreover, once the split-nut 210 is engaged with the threads 209, the bridge plug mandrel 202 may also be shifted in either longitudinal direction.

Although the equalizing valve shown in FIG. 2 may be .arranged as previously described in conjunction with FIG. 1, the slidable valve member 21S is arranged to be normally biased upwardly by a compression spring (not shown) engaged between the lower end of the valve member and a shoulder (not shown), on the mandrel 202 of the bridge plug. Thus, whenever the overshot 200 has been completely disposed over the fishing neck 201 a `downwardly directed shoulder 219 slightly above the cutting teeth 217 on the overshot will engage the upper end of the slidable valve member 21S and force it downwardly to overcome the bias of the spring (not shown) around the mandrel 202. Whenever the overshot is removed, this same spring (not shown) will urge the slidable valve member 218 upwardly to a port-closed position where its upper end engages the lower end 220 of the tubular outer member 204.

Turning now to FIG. 3, a typical bridge plug 300 is shown set in place within a cased well bore 301. Elastomeric packer cups 302, 303 are oppositely directed so that one or the other will always be sealingly engaged with the casing 304 whenever there is a pressure differential across the bridge plug 300 from either direction. Similarly, expanders and slips 305 and 306 are oppositely :directed so that one set or the other will cooperate to prevent the bridge plug 300 from -being shifted by such pressure differentials. An equalizing valve 307 is arranged to function as those previously described.

A fixed lug 303 -projecting inwardly from the housing 309 is cooperatively confined within a typically arranged T-shaped slot 310 in the mandrel 311. Whenever the mandrel 311 is to be secured from shifting, the lug 308 is confined within a short longitudinal slot portion 312; and to free the mandrel for shifting to actuate either the slips 305 or 306, the mandrel 311 is rotated to pass the lug through a horizontal branch slot portion 313 and into alignment with an elongated longitudinal slot portion 314.

Thus, it `will be seen that when the bridge plug 300 is to be retrieved, the mandrel 311 must first :be rotated as it is shifted longitudinally to bring the mandrel to a neutral position where the branch slot portion 313 is aligned with the housing lug 30S. Then to resecure the mandrel 311, the mandrel is rotated to shift the elongated slot portion 314 away from the lug 308 and reconfine the lug within the sort slot portion 312.

Accordingly, when the overshot 315 and fishing neck 316 depicted in FIG. 3, are arranged as the overshot 100 and fishing neck 101 previously described in conjunction with FIG. l, the overshot 100 is rotated as it is brought down over the fishing neck 101 to cut away debris therearound. As already described, so long as the inner member 108 is in its lowermost position, the overshot 100 is free to rotate in one direction around the fixed fishing neck 101. The clutch discs 113, 114, however, will transmit torque in the clockwise direction so the mandrel 311 can be rotated to bring the housing lug 308 into the branch slot portion 313 and then into the short slot portion 312. It will be noted that by virtue of the disc teeth 116 (FIG. l) clockwise torque will lbe continuously applied to the mandrel 311 as it is being shifted either upwardly or downwardly. Thus, should it be necessary to hun-t for the branch slot portion 313 as the mandrel 311 is torqued, the housing lug 308 will be held against that side of the long slot portion 314 which opens into the branch slot portion 313 and ensures that the branch slot portion will be found quickly. Then, once the mandrel 311 is secured, the bridge plug 300 can be retrieved.

In a similar fashion, when the overshot 315 and fishing neck 316 depicted in FIG. 3 are arranged as those previously described in FIG. 2, the overshot 200 is rotated as it is brought over the fishing neck 201. So long as the torque applied to the overshot 200 is in excess of a predetermined magnitude, the rings 212 of clutch 211 will slip relative to the rings 213 to allow the overshot to rotate relative to the fixed fishing neck 201. It will be appreciated, of course, that the frictional restraint between rings 212, 213 will be governed lby the spring 214. Moreover, this restraint will lbe sufficient to allow unjaying and rejaying of the bridge plug mandrel 311 :but not so great that the entire bridge plug 300 will be rotated relative to the casing 304.

Thus, when the bridge plug mandrel 311 is to be rejayed to allow the bridge plug 300 to be retrieved, the overshot 200 is rotated with a torque less than the abovement-ioned predetermined magnitude so as to again reconfne housing lug 308 within the short slot portion 312.

Accordingly, it will be appreciated that the above-described embodiments illustrate new and improved overshots having various clutching devices provided therewith that enable an overshot to be continually rotated relative to the fishing neck for cutting away accumulated debris above a bridge plug so that the overshot may subsequently be positively reengaged With the fishing neck on a bridge plug. Moreover, these clutching devices allow the overshots to be selectively secured to the fishing neck so that torque may be applied to a bridge plug mandrel as needed for releasing the bridge plug. Furthermore, these clutching devices enable the overshots to be positively coupled to the bridge plug so that the mandrel thereof can be shifted in either longitudinal direction either without or in conjunction with rotation of the mandrel. Thus, it has been shown that with these devices, a positive engagement may be made with a bridge plug Without sacrificing the ability to apply positive torque as well as longitudinal forces to the mandrel of the bridge plug.

While the particular embodiments of the present invention have been shown and described, it is apparent that changes and modifications may be made without departing from this invention in its broader aspects; and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

What is claimed is that:

1. In apparatus for retrieving a Well tool having an upright body and releasably secured in a well bore: a rotatable tubular member adapted for connection to a tubing string and having cutting means thereon adapted for rotatively cutting away debris around an upright welltool body; first and second relatively rotatable members fitted together and adapted for reception by said tubular member, said first member being adapted for connection to an upright Well-tool body; first means releasably securing said second member co-rotatively Within said tubular member; and second means selectively operable by rotation of said tubular member, said second means having a first torque characteristic funcition for co-rotatively securing said fitted members to one another and a second torque characteristic function for permitting relative rotation between said fitted members, said second means including first and second annular discs having coengaged opposed surfaces and disposed between said fitted members, said first disc being co-rotatively secured to said first member and said second disc being co-rotatively secured to said second member, and spring means urging said discs into co-engagement.

2. In apparatus for retrieving a well-tool having an upright body and releasably secured in a well bore: a rotatable tubular member adapted for connection to a tubing string and having cutting means thereon adapted for rotatively cutting away debris around an upright well-tool body; first and second relatively rotatable and slidably telescoped members adapted for reception by said tubular member, said first member being adapted for connect-ion to an upright well-tool body, said second member being arranged to shift longitudinally in relation to said first member between spaced-apart positions; first means releasably securing said second member corotatively within said tubular member; and second means selectively operable by shifting of said tubular member for co-rotatively securing said telescoped members to one another whenever said second member is in one of said positions and co-rotatively securing said telescoped members against relative rotation in only one rotative direction whenever said second member is in the other of said positions.

3. In apparatus for retrieving a well-tool having an upright body and releasably secured in a well bore: a rotatable tubular member adapted for connection to a tubing string and having cutting means thereon adapted for rotatively cutting away debris around an upright welltool body; first and second relatively rotatable and slidably telescoped members adapted for reception by said tubular member, said first member being adapted for connection to an upright well-tool body, said second member being arranged to shift longitudinally in relation rto said first member between spaced-apart first and secand positions, said first and second members respectively having a first pair of opposed surfaces adapted to be coengaged whenever said second member is in said first position and a second pair of opposed surfaces adapted to be co-engaged Whenever said second member is in said second position; means releasably securing said second member `co-rotatively within said tubular member; first, means selectively operable by shifting of said tubular member for co-rotatively securing said telescoped members to one another whenever said second member is in said first position including a first set of co-engageable complementary teeth disposed around each of said first pair of opposed surfaces; and second means selectively `operable by shifting of said tubular member for co-rotatively securing said telescoped members against relative rotation in only one rotative direction whenever said sec ond member is yin said second position including a second set of co-engageable complementary teeth disposed around each of said second pair of opposed surfaces.

4. In apparatus for retrieving a well-tool having an upright body and releasably secured in a Well bore: a rotatable tubular member adapted for connection to a tubing string and having cutting means thereon adapted for rotatively cutting away debris around an upright well-tool body; first and second relatively rotatable and slidably telescoped members adapted for reception by said tubular member, said first member having an offset portion and being adapted for connection to an upright well-tool body, said second member being arranged to shift longitudinally in relation to said first mem-ber between spacedapart first and second positions; first and second annular discs having co-engaged surfaces disposed between said telescoped members and spaced-apart from said offset portion, said first disc being slidably secured co-rotatively to said first member, said second disc being disposed intermediate said first disc and said offset portion and corotatively secured to said second member; spring means urging said discs into co-engagement; means releasably securing said second member co-rotatively within said tubular member; first means selectively operable by shifting of said tubular member for co-rotatively securing said telescoped members to one another whenever said second member is in said first position including a first set of co-engageable complementary teeth disposed around each of the opposed surfaces of said offset'portion and said second disc; and second means selectively operable by shifting of said tubular member for co-rotatively securing said telescoped members against relative rotation in only one rotative direction whenever said second member is in said second position including a second set of co-engageable complementary teeth disposed around each of said co-engaged opposed surfaces of said discs.

5. In apparatus for retrieving a well-tool having an upright body and releasably secured in a well bore: a rotatable tubular member adapted for connection to a tubing string and having cutting means thereon adapted for rotatively cutting away debris around an upright welltool body; first and second relatively rotatable members fitted together and adapted for reception by saidtubular member, said first member being adapted for connection to an upright well-tool body; first means releasably securing said second member `co-rotatively within the said tubular member; and second means responsive to torque and selectively operable by rotation of said tubular member for co-rotatively securing said fitted members to one another upon rotation of said tubular member at a torque less than a predetermined magnitude and releasable upon rotation of said tubular member at a torque greater than said predetermined magnitude, whereby said tubular member can be rotated relative to an upright well-tool body.

6. In apparatus for retrieving a well-tool having an upright body and releasably secured in a well bore: a rotatable tubular member adapted for connection to a tubing string and having cutting means thereon adapted for rotatively cutting away debris around an upright welltool body; first and second relatively rotatable members fitted together and adapted for reception by said tubular member, sa-id first member being adapted for connection to an upright well-tool body; first `means releasably securing said second member co-rotatively within the said tubular member; and second means responsive to torque and selectively operable by rotation of said tubular member for co-rotatively securing said fitted members to one another upon rotation of said tubular member at a torque less than a predetermined magnitude and releasable upon rotation of said tubular member at a torque greater than said predetermined magnitude, whereby said tubular member can be rotated relative to an upright well-tool body, said second means including first and second annular discs having co-engaged opposed surfaces fitted between said telescoped members, said first disc being corotatively secured to said first member and said second `disc being `co-rotatively secured to said second member, and spring means urging said discs into co-engagement.

7. A well packer sized and adapted for reception in a well bore for packing-off the well lbore comprising: a housing member; a body member having an offset portion proximate its upper end and movably mounted Within said housing member; packing means mounted around one of said members and adapted for expansion into sealing engagement with a well bore; wall-engaging means mounted on said housing; means responsive to longitudinal shifting of `said body member for extending said wall-engaging means into engagement with a wall of a Well bore; first coupling means releasably securing said body member to said housing member and releasable by rotation of said body member to free said body member for longitudinal shifting; and second coupling means adapted for releasably coupling said body member to a tubing string, said second coupling means including a rotatable tubular member connectable to a tubing string and having cutting means thereon for rotatively cutting away debris around said body member, said tubular member being sized and adapted to receive said body member, a rotatable coupling member slidably and telescopically mounted on said body member, said coupling member being arranged to shift longitudinally in relation to said body member between spaced-apart first and second positions, first and second annular discs having co-engaged opposed surfaces disposed between said telescoped members and spaced-apart from said offset portion, said first disc being slidably secured co-rotatively to said first member, said second disc being disposed intermediate said rst disc and said offset portion and co-rotatively secured to said second member; spring means urging said discs into co-engagement; means releasably securing said coupling member co-rotatively to said tubular member for shifting said coupling member between said positions and for rotating said coupling member, first means selectively operable by shifting of said tubular member for co-rotatively securing said coupling member to said body member whenever said coupling member is in said first position including a rst set of co-engageable complementary teeth on each of the opposed mating surfaces of said second disc and said offset portion, and second means selectively operable by shifting of said tubular member for co-rotatively securing said coupling member against rotation in only one direction relative to said body member whenever said coupling member is in said second position including a second set of co-engageable complementary teeth on each of the opposed co-engaged surfaces of said discs.

8. A well packer sized and adapted for reception in a well bore for packing-off the well bore comprising: a housing member; a body member movably mounted within said housing member; packing means mounted around one of said members and adapted for expansion into sealing engagement with a well bore; wall-engaging means mounted on said housing; means responsive to longitudinal shifting of said body member for holding said wallengaging means in engagement against a Wall of a Well bore; first coupling means releasably securing said `body member to said housing member and releasable by rotation of said body member to free said body member for longitudinal shifting; and second coupling means adapted for releasably coupling said body member to a tubing string, sa-id second coupling means including a rotatable tubular member connectable to a tubing string and having cutting means thereon for rotatively cutting away debris around said body member, said tubular member being sized and adapted to receive said body member, a rotatable coupling member tted around said body member and operatively received within said tubular member, means releasably secu-ring said coupling member corotatively to said tubular member, and means responsive to torque and selectively operable by rotation of said tubular member for co-rotatively securing said coupling member to said body member upon rotation of said tubular at a torque less than a predetermined magnitude and releasable upon rotation of said tubular member at a torque greater than said predetermined magnitude, whereby said tubular member can be rotated relative to said body member without rotating said wall-engaging means relative to the wall of the well bore.

9. A well packer sized and adapted for reception in a well bore for packing-off the well bore comprising: a housing member; a body member movably mounted within said housing member; packing means mounted around one of said members and adapted for expansion into sealing engagement with a well bore; wall-engaging means mounted on said housing; means responsive to longitud-inal shifting of said body member for holding said wallengaging means in engagement against a. wall of a well bore; first coupling means releasably securing said body member to said housing member and releasable by rotation of said body member to free said body member for longitudinal shifting; and second coupling: means adapted for releasably coupling said body member to a tubing string, said second coupling means including a rotatable tubular member connectable to a tubing string and having Cutting means thereon for rotatively cutting away debris around said body member, said tubular member being sized and adapted to receive said body member, a rotatable coupling member fitted around said body member and operatively received within said tubular member, means releasably securing said coupling member co-rotatively to said tubular member, means responsive to torque and selectively operable by rotation of said tubular member for co-rotatively securing said coupling member to said body member upon rotation of said tubular member at a torque less than a predetermined magnitude and releasable upon rotation of said tubular member at 'a torque greater than said predetermined magnitude, said torque-responsive means including `first and second annular discs having co-engaged opposed surfaces disposed between said coupling member and said body member, said rst disc being co-rotatively secured to said body member and said second disc being co-rotatively secured to said coupling member, `and spring means urging said discs into co-engagement.

References Cited by the Examiner UNITED STATES PATENTS 2,762,438 9/1956 Naylor 294-8634 2,804,151 8/1957 Le Bus 175-315 X 2,887,162 5/1959 Le Bus 294-8634 2,998,072 8/1961 Crowe 166-123 3,005,506 10/1961 Le Bus 166-99 X 3,070,170 12/1962 Le Bus et al. 166-99 X CHARLES E. OCONNELL, Primary Examiner.

D. H. BROWN, Assistant Examiner. 

2. IN APPARATUS FOR RETRIEVING A WELL-TOOL HAVING AN UPRIGHT BODY AND RELEASABLY SECURED IN A WELL BORE: A ROTATABLE TUBULAR MEMBER ADAPTED FOR CONNECTION TO A TUBING STRING AND HAVING CUTTING MEANS THEREON ADAPTED FOR ROTATIVELY CUTTING AWAY DEBRIS AROUND AN UPRIGHT WELL-TOOL BODY; FIRST AND SECOND RELATIVELY ROTATABLE AND SLIDABLY TELESCOPED MEMBERS ADAPTED FOR RECEPTION BY SAID TUBULAR MEMBER, SAID FIRST MEMBER BEING ADAPTED FOR CONNECTION TO AN UPRIGHT WELL-TOOL BODY, SAID SECOND MEMBER BEING ARRANGED TO SHIFT LONGITUDINALLY IN RELATION TO SAID FIRST MEMBER BETWEEN SPACED-APART POSITIONS; FIRST MEANS RELEASABLY SECURING SAID SECOND MEMBER COROTATIVELY WITHIN SAID TUBULAR MEMBER; AND SECOND MEANS SELECTIVELY OPERABLE BY SHIFTING OF SAID TUBULAR MEMBER FOR CO-ROTATIVELY SECURING SAID TELESCOPED MEMBERS TO ONE ANOTHER WHENEVER SAID SECOND MEMBER IS IN ONE OF SAID POSITIONS AND CO-ROTATIVELY SECURING SAID TELESCOPED MEMBERS AGAINST RELATIVE ROTATION IN ONLY ONE ROTATIVE DIRECTION WHENEVER SAID SECOND MEMBER IS IN THE OTHER OF SAID POSITIONS. 